Gyrating device



Jan. 16, 1951 E. A. EBERT 2,537,980

GYRATING DEVICE Filed April 16, 1947 2 Sheets-Sheet l INVENTOR E. A. EBERT GYRATING DEVICE Jan. 16, 1951 2 Sheets-Sheet 2 Filed April 16, 1947 lNVENTOR Patented Jan. 16, 1951 UNITED STATES PATENT OFFICE 14 Claims.

This invention relates to vibratory screens of the type which are vibrated with an oscillatory motion by a single eccentric shaft mounted at or near the center of gravity of the movable screen body.

An object of the invention is to provide an improved means of restraining the movable screen frame, against rotation or tilting about either the stationary axis or the eccentric axis of the eccentric shaft, such rotation being urged by the friction of the bearings or sudden loads thrown on the screen at either side of the eccentric shaft.

Another object is to provide a means which resists this tendency to rotation without putting additional strain or load on the bearings.

Another object i to provide a holding means which permits free movement of the screen in a desired path and resist any movements in a path undesirable to good screening.

A further object is to provide a screening unit having simple, duplicate, and interchangeable parts, which can be made on ordinary machines at low cost.

Another object is to provide an improved, power operated screen, which will have maximum screening effectivness with, a minimum of power consumption, and which may operate at relatively high speeds with a minimum of instability, and which will be relatively simple, compact, durable and inexpensive.

A further object is to generally simplify and improve the operation of screens having oscillatory or gyratory movements of small amplitude.

Other objects and advantages will appear from the following description of one embodiment of the invention, and the novel features will be particularly pointed out hereinafter in the appended claims.

In the accompanying drawings:

Fig. 1 is a side elevation of a vibratory screen constructed in accordance with the invention, showing the stabilizing means.

Fig. 2 is a top plan of the same, showing stabilizing means on both sides of the screen body.

Fig. 3 i a diagrammatic showing of what is believed to be the principal involved in this invention.

Fig. 4 is a vertical sectional elevation of the same taken along the line 4-4 of Fig. 2 showing the stabilizing means, certain parts being in section.

Fig. 5 is a vertical sectional elevation of the same, taken along the line 5-5 of Fig. 4, the eccentric being in the up position.

6 a ho iz nta es f the sam taken along the line 6-5 of Fig. 4 with the eccentric and its associated parts in a left hand position in full lines and a right hand. position shown in dotted lines.

In the illustrated embodiment of the invention the stationary screen frame or base part I (Figs. 1 and 2) includes the usual side channels or beams 2 spaced from each other by stringers 3 at their front and rear ends.

An eccentric shaft 4 is mounted in suitable antifriction bearings 5 seated on the channels 2. The shaft 4 has eccentric portions 6, upon which the live screen body or separate screen frame part or element 1 is mounted for its circulatory motion. Another pair of anti-friction bearings B (only one being shown in Fig. 5) is provided on each eccentric portion 6 of shaft 4 for the live screen body 1. A pulley I0 is provided at one end of the shaft 4 for connection to operating power.

This particular type of screen construction has been and is a very popular and successful machine, and various forms of stabilizing devices have been used to prevent the live screen body from teetering or oscillating on its single shaft. If the stabilizer used does not restrain the teetering sufficiently, such as when a load of the material to be screened is suddenly thrown upon the screens of the screen body 7 at the'feed end which would always be on one side or the other of the eccentric shaft i, teetering occurs and a periodic vibration is set up which is ruinous to the bearings 5 and 8 and also to the buildings in which the machine is installed. These sudden loads thrown on the screen 1 might be as high as a ton or more which in itself is not as bad as the ruinous vibration set up in the machine because of the teetering frequencies.

Teetering also spoil the circulatory path tending to divide it into its components, i. e., a horizontal movement at one end and a vertical. movement at the opposite end. Since the eccentricity is usually in the neighborhood of only A; or A of an inch a small amount of freedom in the stabilize spoils the screening action of the machine.

This invention, therefore, provides a stabilizing means or mechanism which freely permits the live screen body I to gyrate about its eccentric shaft 4 but effectivelyresists any teetering or rotation about either the eccentric portions 6, or the concentric portions of the eccentric shaft4 and is described as follows:

The, side channels 2 have mounted on their upper face, upstanding, angle brackets 20, one on each side of the adjacent shaft bearings 5.

Vertically rigid but horizontally flexible members 2| are clamped to the vertical faces of the angle brackets 20 by clamping plates 22 and cap screws 23. The members 2! project inwardly toward the live screen body 1 and at a substantial distance from brackets 26 are securely clamped to vertical faces 24 (Fig. 4) of an intermediate torsion ring, spider or rigid interponent 25 by clamping plates 25 and cap screws 21.

The torsion interponent 25 is a floating member and is located approximately concentric with the eccentric shaft bearing and of course, extends more than half way around the shaft and preferably is a ring that surrounds the eccentric shaft A.

Horizontal faces 34 (Figs. 4 and 5), top and bottom, are also provided on the torsion ring '25 and horizontally rigid but vertically flexible members 3! are clamped to these faces 3% by plates 32 and cap screws 33.

The members 3! also project inwardly toward the live screen body 2' and, at their edges opposite from ring 25, are clamped to angle brackets 3'5 by clamping plates 35 and cap screws 31.

When the shaft 4 is rotated by the pulley it] its eccentric portions 5 drive the screen body I in a circular or gyratory path, and because members 3! are mounted on the screen body l through brackets 35 the inner ends of these members 3i also take a circular path.

The opposite edges of members 3| that are connected to the torsion ring 25, because of reasons explained later, only move in a horizontal path. Therefore members 3! will flex vertically to permit the vertical component of the circular path of the body I.

The outer ends of the members 2|, since they are connected to the brackets 20 on the side channels 2 are of course stationary. The inner ends of the members 2! that are connected to the torsion ring 25 move freely in a horizontal direction and are therefore made flexible in a horizontal direction.

The torsion ring 25 is moved horizontally by the members 3! since they are rigid horizontally and flex only vertically.

Components of a circular movement are a vertical movement and a horizontal movement of the same amountconseo uently it is necessary to have the members 35 allow or flex for vertical movement of the live screen frame 1 and the members 2! allow or flex for horizontal movement of said screen frame. This permits the live screen frame to be gyrated by its eccentric 6 with out resistance except for the flexing of the members 2i and 3!. Also it is necessary to have the members .3! rigid in a horizontal plane and the members 2! rigid in a vertical plane to resist teeteringor rotation about the shaft ii to accomplish the stabilizing effect desired.

Let us assume that a load has been imposed on the right hand end of the live screen frame I in Fig. 1. This strains the upper member 3! to the right and the lower member 3! to left and through their connections to the torsion ring 25 tendsto rotate this ring 25 clockwise. This can be followed by reference to Fig. 3. This ring 25 having the members 2! on either side, bears downwardly on the right hand member 2! and its bracket 20 and upwardly on the left hand member 2! and its bracket 2i). Since all of the aforementioned parts are rigid in the direction of this load, and since the brackets 20 are rigidly.

mounted on the stationary frame members 2, the load is borne by the stationary frame members 2 through these connections. A reversal of load to the left hand side of frame 1 in Fig. 1 will likewise be borne and transmitted to the stationary frame members 2. The live frame 1 and the stationary frame members 2 are thus always in strict parallelism no matter where the load might be on the live frame 1.

It willbe clearly seen in Fig. 5 that vertical movement of the live screen frame I can take place in respect to the stationary channel member 2. Also in Fig. 6 it will be observed that horizontal movement of the live screen frame I and the torsion ring 25 together can take place in respect to the stationary channel member 2. These two movements, i. e. vertical and horizontal movement, allow the gyration of the screen about shaft A to take place.

The members 2i and 3! are preferably made of spring metal only a few thousandths of an inch thick and it would seem at first sight that they might distort or twist about the shaft 4, since we must assume that the strain is a rotational strain about the shaft 4, but this does not occur; in other words movement (rotation) does not take place, so that the torsional strain can be separated into components of horizontal and vertical strains as will appear when looking at Fig. 4.

If desired the members 3i and 2! could be elongated or extended (looking at Fig. 4) until their ends or edges meet, and the torsion ring 25 then would take the form of a square. This would give greater torsional resistance if necessary on heavier constructions.

The usual fly Wheels 40 (Figs. 4 and 5) and counter balances M are provided on each side of the live screen frame '3 on the concentric portions of the shaft i, to counterbalance the weight of the screen frame and as illustrated in Fig. 5 the torsion rings 25 have sufficient inside clearance or diameter to clear these fly wheels.

Fig. 3 shows in diagrammatic form, the principal members, having like reference numerals to those already described, and their directions of movement by arrows. For simplicity, the direction of their resilience has been indicated by the curved arrows on members 2! and 2 I.

It will be understood that various changes in the details, materials and arrangements of parts, which have been herein described and illustrated in order to explain the nature of the invention, may be made by those skilled in the art within the principle and scope of the invention as expressed in the appended claims.

I claim:

1. A gyrating device comprising a base part, a separate movable frame part, means for positively gyrating said movable part about a selected axis relatively to said base part, and additional stabilizing means inter-posted between said base part and movable part for preventing rocking of said movable part about an axis approximately coincident with said axis of yration, said stabilizing means comprising a rigid loop-like interponent encircling said selected axis, vertically flexible and horizontally rigid elements connecting said interponent and one of said parts and horizontally flexible and vertically rigid elements connecting said interponent and the other of said parts.

2. A gyrating device comprising a base having S a-tea members, a separate movable element having a broad surface, a rotatable shaft extending between said members generally para separate movable part, power operated means acting between said base and movable parts for gyrating said movable part bodily relatively to said base part about a selected axis, a relatively rigid interponent encircling and spaced from said gyrating means, horizontally rigid and vertically flexible means connecting said interponent to one of said parts, and vertically rigid and horizontally flexible means connecting said interponent to the other of said parts, said interponent being spaced from and free to move relatively to both of said parts.

4. A gyrating device comprising a base part, a separate movable part, power operated means acting between said base and movable parts for gyrating said movable part bodily relatively to said base part about a selected axis, a relatively rigid interponent arranged around said axi and spaced from said gyrating means and said parts, a flexible plate connected at one edge to said interponent and at its opposite edge to said movable part, another and separate flexible plate connected at one edge to said interponent and at its opposite edge to said base part, said plates extending generally parallel to said axis and being disposed with the planes of their faces at approximately right angles to each other, whereby said movable part may move back and forth in one direction by the flexing of one of said plates, and in another direction at right angles thereto by the flexing of the other of said plates.

5. A gyrating device comprising a base part, a separate movable part, power operated means acting between said base and movable parts for gyrating said movable part bodily relatively to said base part about a selected axis, a relatively rigid interponent arranged around said axis and spaced from said gyrating means and said parts, flexible elements connecting said interponent and said movable part, additional flexible elements connecting said interponent and said base part, each of said elements extending generally parallel to said axis and being flexible freely in one transverse direction and resisting flexing in a crosswise transverse direction, the elements conmeeting said interponent to one of said parts flexing freely in one direction and crosswise of the direction of free flexing of the other elements, said interponent being spaced from and free to move relatively to both of said parts.

6. A gyratory device comprising a base, a movable frame, means for gyrating said movable frame relatively to said base about a selected axis, stabilizing means comprising a pair of vertically rigid but horizontally flexible members projecting toward the movable frame from the base and generally parallel to said axis, a rigid torsion ring located around said axis and between and spaced from said movable frame and said base and connected to the projecting parts of said members, a pair of horizontally rigid but vertically flexible members projecting from said torsion ring towards and connected to said movable frame and 6 generally parallel to said axis, said stabilizing means maintaining a parallel relationship between said base and said movable frame, during gyrations of said movable frame.

7. A gyratory device comprising a base, a movable frame, means for gyrating said movable frame relatively to said base about a selected axis, stabilizing means comprising a floating member having a pair of resilient plates projecting toward and connected to said movable frame and another pair of resilient plates projecting toward and connected to said base, said first pair of plates being disposed approximately about said member from said second pair of plates, all of said plates projecting generally parallel to said axis and being flexible in directions crosswise of the axis of gyration but rigid in a direction around said axis, to maintain the movable frame and said base in parallelism during yrations of said frame.

8. A gyratory device having a base, a movable frame, a rotatable shaft journalled on said base and having an eccentric portion journalled to said frame, a torsion member surrounding and spaced from said eccentric shaft portion and located between said base and said frame; said torsion member having one pair of resilient members extending toward said base and another pair at right angles to the first extending toward said frame, one of said pairs of members being resiliently flexible in a horizontal direction and relatively rigid vertically, and the other pair of members being resiliently flexible in a vertical direction and relatively rigid horizontally, and both pairs extending in directions generally parallel to said shaft.

9. A gyrating device comprising a base part, a separate relatively movable part, power operated means acting between said base and movable parts for gyrating said movable part bodily relatively to said base part about a selected axis, a

relatively rigid interponent extending more than half way about said axis, a plurality of resiliently flexible flat plates disposed generally parallel to said axis of gyration and each connected at one end to said interponent, one portion of the plates being disposed with their face planes at approximate right angles to the face planes of the other plates, and connected at their opposite ends to one of said parts, said other plates being connected at their ends opposite from the interponent to the other of said parts.

10. A gyrating device comprising a base, a. separate relatively movable element, power operated means for gyrating said element bodily relatively to said base about a selected axis, a relatively rigid interponent extending more than half way around said axis, resiliently yieldable means interposed between said interponent and said element, additional resiliently yieldable means interposed between said interponent and said base, the direction of yield of one of said yieldable means being solely crosswise of the direction of yield of the other of said yieldable means, and both of the directions of yield being crosswise of said axis of gyration.

11. A gyrating device comprising two separate relatively movable parts, means having an eccentric connection acting between said parts for bodily gyrating one part relatively to the other about a selected axis, a floating, rigid interponent encircling said axis and spaced from both of said parts, two pairs of members projecting from said interponent in the same general direction in which said axis extends, the members of one pair being on opposite sides of said axis and connected at their projecting ends to one of said parts, and members of the other pair being on opposite sides of said axis and connected at their projecting ends to the other of said parts, each pair of members being freely flexible solely in one transverse direction, and the direction of flexing of one pair being transversely crosswise of the direction of flexing of the other pair.

12., The device substantially as set forth in claim 11 in which said members are flexible, resilient plates, with the plates of each pair generally parallel, and the faces of the plates of each pair being at approximately right dihedral angles to the faces of the plates of the other pair.

13. In a device of the character described, a base part, a separate relatively movable frame part, means for gyrating said frame part about a selected axi relatively to said base part, and stabilizing means interposed between said base part and frame part and preventing any rocking of said frame part about an axis approximately coincident with said axis of gyration, said stabilizing means comprising a rigid member substantially encircling said vertically flexible but horizontally rigid elements projecting from said member and connected to one of said parts at opposite sides of the axis of gyration, and horizontally flexible but vertically rigid elements projecting from said member at opposite sides of the axis of gyration, and connected to the other of said parts, said elements all projecting from said member in directions generally parallel to said axis.

14. A gyrating device having a stationary base, a live frame, means for gyratin said frame about a selected axis relatively to said base, and stabilizing means interposed between said base and said frame to maintain the same frame parallel to the said base throughout its gyrations, said stabilizing means comprising a rigid, loop-like interponent substantially encircling said axis, a pair of flexible generally parallel plates projecting from said interponent at opposite sides of said axis and connected to said frame, another pair of generally parallel plates projecting from said interponent also at opposite sides of said axis but disposed about degrees angularly about said axis from the first pair of plates, and connected to said base, each of said plates being freely flexible in one transverse direction only, the direction of flexibility of one pair of plates being crosswise of the direction of flexibility of the other pair, and the direction of projection of all plates from said interponent being generally parallel to said axis, one pair of plates flexing freely in one transverse direction and resisting flexure in the other transverse direction, the other pair of plates flexing freely in the transverse direction in which said one pair is resistant to flexure, and resisting fiexure in the transverse direction in which said one pair flexes freely.

EDWARD A. EBERT.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,923,229 Robins Aug. 22, 1933 2,042,072 rtobins May 26, 1936 2,053,585 Toepler Sept. 8, 1936 2,140,172 Royer Dec. 13, 1938 2,258,550 Frese Oct. 7, 1941 2,307,098 Adrianson Jan. 5, 1943 2,309,171 De Kanski Jan. 26, 1943 FOREIGN PATENTS Number Country Date 431,928 Germany July 19, 1926 661,893 Germany June 29, 1938 

